1. Field of the Invention
This invention relates to an image processing apparatus and an image processing method, both designed to process the pixel outputs of an imaging element in which some pixels are used as focal point detecting pixels of a phase-difference type, and also relates to a non-transitory storage medium that stores an image processing program.
2. Description of the Related Art
An imaging apparatus that utilizes some of the pixels of an imaging element as phase-difference detecting pixels, is proposed in, for example, Japanese Patent No. 3592147. In the imaging apparatus proposed in Japanese Patent No. 3592147, some of the pixels of the imaging element are used as phase-difference detecting pixels, and light beams coming from an object through different pupil regions symmetric to the optical axis of the photographing lens are focused at the phase-difference detecting pixels. The phase-difference detecting pixels therefore detect the phase difference between the light beams, thereby determining the focusing state of the photographing lens.
A part of each phase-difference detecting pixel is, for example, shielded from light and receives only one of the light beams coming through the different pupil regions of the photographing lens. Thus, the phase-difference detecting pixels are deficient, and cannot be used as-is to form an image. In the imaging apparatus proposed in Jpn. Pat. Appln. KOKAI Publication No. 2010-062640, the outputs of the phase-difference detecting pixels are therefore adjusted in terms of gain, or interpolated by using the signals output from the pixels adjacent to the phase-difference detecting pixels.